Advocates of the agreement have characterized a congressional vote of disapproval as the opening salvo of the next Middle East war. In reality, a “no” vote may have powerful symbolic value, but it has limited practical impact according to the law. It does not, for example, negate the administration’s vote at the UN Security Council in support of the deal, which sanctified the agreement in international law. Nor does it require the president to enforce U.S.sanctions against Iran with vigor. Its only real meaning is to restrict the president’s authority under the law to suspend nuclear-related sanctions on Iran.
Here’s the catch: By the terms of the nuclear agreement, the president only decides to suspend those sanctions after international inspectors certify that Iran has fulfilled its core requirements. In other words, congressional disapproval has no direct impact on the actions Iran must take under the agreement to shrink its enriched-uranium stockpile, mothball thousands of centrifuges, and deconstruct the core of its Arak plutonium reactor. Most experts believe that process will take six to nine months, or until the spring of 2016.
Why would Iran do all of these things if it can’t count on the United States to suspend sanctions in response? While it’s impossible to predict with certainty how Iranian leaders would react to congressional disapproval of the agreement, I’d argue chances are high that they would follow through on their commitments anyway, because the deal is simply that good for Iran. After Iran fulfills its early obligations, all United Nations and European Union nuclear-related sanctions come to an end. They aren’t just suspended like U.S. sanctions—they are terminated, presenting Iran with the potential for huge financial and political gain.
The “deal or war” thesis propounded by supporters of the agreement suggests that Iran, in the event of U.S. rejection of the deal, would prefer to bypass that financial and political windfall and instead put its nuclear program into high gear, risking an Israeli and American military response. But that volte-face makes little sense, now that Iran has painstakingly built a nuclear program that is on the verge of achieving the once-unthinkable legitimacy that comes with an international accord implicitly affirming Iran’s right to unrestricted enrichment in the future. In such a scenario, Iran would reap an additional benefit in continuing to implement the agreement: The United States, not Iran, would be isolated diplomatically.